Collection tube assembly



FIG. 1 is a front perspective view of a collection tube assembly showing my new design;

FIG. 2 is a side elevation view of the collection tube assembly shown in FIG. 1;

FIG. 3 is a top plan view of the collection tube assembly shown in FIG. 1; and,

FIG. 4 is a bottom plan view of the collection tube assembly shown in FIG. 1.

The broken lines in the figures depict portions of the collection tube assembly that form no part of the claimed design. 

CLAIM The ornamental design for a collection tube assembly, as shown and described. 